Blizzard Entertainment reported on Thursday that Battle.net, its proprietary game network, has been hacked, and some user information has been stolen, though the company has seen no evidence that accounts or credit cards are at risk.
The stolen information includes email addresses for users outside of China, and for players on North American servers specifically, that data also includes the answers to personal security questions and information relating to mobile and dial-in Battle.net authenticators. This affects players across all of Blizzard's Battle.net properties, including StarCraft II, Diablo III, and World of Warcraft.
In a post on the official Blizzard website, studio president Mike Morhaime said that the company does not think the stolen data would allow anyone to gain access to another users' Battle.net account, nor does it think any credit card data has been accessed.
While Blizzard isn't aware of any compromised accounts so far, the company is urging North American users to change their passwords, and will be prompting all players to update their personal security questions.